Mechanically attached thermal protection system

Abstract

A mechanically attached thermal protection system (MATPS) includes an insulating tile having a top surface, a bottom surface, and a plurality of access holes that extend through the insulating tile from the top surface to the bottom surface. A plurality of brackets include a first end attached to the insulating tile and a second end including a mounting hole therethrough, the second end being positioned proximate the bottom surface of the insulating tile. A plurality of fasteners are positioned proximate the bottom surface of the insulating tile and at least partially positioned within one of the access holes so as to be accessible from the top surface of the insulating tile through one of the plurality of access holes. A MATPS including a plurality of air channels within the insulating tile and a method for sealing these air channels to those within an adjacent structure is also described herein.

The invention claimed is: 
     
       1. A mechanically attached thermal protection system, comprising:
 an insulating tile comprising a top surface, a bottom surface, and a plurality of access holes that extend through the insulating tile from and through the top surface to and through the bottom surface; 
 a plurality of brackets comprising a first end attached to the insulating tile and a second end comprising a mounting hole therethrough, the second end being positioned proximate the bottom surface of the insulating tile; and 
 a plurality of fasteners positioned proximate the bottom surface of the insulating tile wherein each fastener is at least partially positioned within one of the access holes and is thereby accessible from the top surface of the insulating tile through one of the plurality of access holes. 
 
     
     
       2. The mechanically attached thermal protection system of  claim 1  for use with a substrate comprising a surface, the thermal protection system further comprising:
 a plurality of studs extending from the surface of the substrate, wherein:
 each stud of the plurality of studs extends through one of the mounting holes in one of the plurality of brackets; and 
 each fastener of the plurality of fasteners secures one of the plurality of brackets to one of the plurality of studs. 
 
 
     
     
       3. The mechanically attached thermal protection system of  claim 1 , wherein:
 the insulating tile comprises a perimeter; and 
 each of the plurality of access holes, each of the mounting holes through the second end of each bracket, and each of the fasteners is within the perimeter of the insulating tile. 
 
     
     
       4. The mechanically attached thermal protection system of  claim 1 , wherein:
 the insulating tile further comprises a plurality of sides; 
 each bracket is an L-shaped bracket; and 
 each bracket is attached to one of the plurality of sides at an attachment point. 
 
     
     
       5. The mechanically attached thermal protection system of  claim 4 , wherein each bracket is attached to one of the plurality of sides at at least two attachment points. 
     
     
       6. The mechanically attached thermal protection system of  claim 4 , further comprising one or more machined, etched, or molded voids within each of the plurality of sides of the insulating tile, wherein a portion of each attachment point is positioned within one of the voids within the sides of the insulating tile. 
     
     
       7. The mechanically attached thermal protection system of  claim 6 , further comprising a plurality of ceramic matrix composite washers, wherein each ceramic matrix composite washer is positioned within one of the voids within the sides of the insulating tile. 
     
     
       8. The mechanically attached thermal protection system of  claim 1  for use with a substrate comprising a surface having a plurality of air inlets therethrough, wherein the insulating tile further comprises:
 a plurality of sides; 
 an inner core; 
 an outer shell, wherein the outer shell forms at least a portion of the top surface, the bottom surface, and the plurality of sides; and 
 a plurality of air channels, wherein each air channel of the plurality of air channels originates at an orifice through the outer shell of the bottom surface of the insulating tile and extends through the inner core of the insulating tile, 
 wherein each air inlet of the plurality of air inlets is in fluid communication with one of the plurality of air channels. 
 
     
     
       9. The mechanically attached thermal protection system of  claim 8 , further comprising a plurality of studs extending from the surface of the substrate, wherein:
 each stud of the plurality of studs extends through one of the mounting holes in one of the plurality of brackets; and 
 each fastener of the plurality of fasteners secures one of the plurality of brackets to one of the plurality of studs. 
 
     
     
       10. The mechanically attached thermal protection system of  claim 9 , further comprising a seal between each of the plurality of air inlets and each of the air plurality of air channels, wherein each seal comprises:
 a circular or oval inner spring seal comprising an arcuate cross section; and 
 an outer compliant ring that physically contacts the spring seal. 
 
     
     
       11. The mechanically attached thermal protection system of  claim 10 , further comprising:
 a recess within the bottom surface of the insulating tile; and 
 a ceramic matrix composite washer positioned within the recess in the bottom surface of the insulating tile, 
 wherein the ceramic matrix composite washer physically contacts the insulating tile and the outer compliant ring. 
 
     
     
       12. The mechanically attached thermal protection system of  claim 8 , further comprising:
 a plurality of capillaries within the inner core that branch from the plurality of air channels; and 
 a plurality of openings at the top surface of the insulating tile that extend through the outer shell, wherein each capillary terminates at one of the plurality of openings at the top surface. 
 
     
     
       13. The mechanically attached thermal protection system of  claim 8 , wherein at least one of the air channels through the inner core of the insulating tile opens into at least one of the access holes. 
     
     
       14. The mechanically attached thermal protection system of  claim 1 , wherein the insulating tile further comprises an inner core and an outer shell wrapped around the inner core, wherein:
 the outer shell forms at least a portion of the top the top surface, the bottom surface, and the plurality of sides; 
 the outer shell comprises a composite comprising ceramic fibers; and 
 the inner core comprises at least one of a ceramic, a silica, an alumina, and a fiber insulation. 
 
     
     
       15. An aircraft having a surface to be protected from a heat source, the aircraft further comprising:
 a plurality of studs extending from the surface; 
 a mechanically attached thermal protection system (MATPS) attached to the surface of the aircraft, wherein the MATPS comprises:
 an insulating tile comprising a top surface, a bottom surface, and a plurality of access holes that extend through the insulating tile from and through the top surface to and through the bottom surface; 
 a plurality of brackets comprising a first end attached to the insulating tile and a second end comprising a mounting hole therethrough, the second end being positioned proximate the bottom surface of the insulating tile; and 
 a plurality of fasteners positioned proximate the bottom surface of the insulating tile wherein each fastener is at least partially positioned within one of the access holes and is thereby accessible from the top surface of the insulating tile through one of the plurality of access holes; 
 
 wherein each stud of the plurality of studs extends through one of the mounting holes in one of the plurality of brackets, and each fastener of the plurality of fasteners secures one bracket of the plurality of brackets to one of the plurality of studs. 
 
     
     
       16. The aircraft of  claim 15 , wherein the surface to be protected is an exhaust output surface. 
     
     
       17. The aircraft of  claim 15 , wherein:
 the insulating tile comprises a perimeter; and 
 each of the plurality of access holes, each of the mounting holes through the second end of each bracket, and each of the fasteners is within the perimeter of the insulating tile. 
 
     
     
       18. The aircraft of  claim 15 , wherein:
 the insulating tile further comprises a plurality of sides; 
 each bracket is an L-shaped bracket; and 
 each bracket is attached to one of the plurality of sides at an attachment point.